OK. I have nearly everything figured out on my new XL, except switching the backs. How do I release the Graflok back assembly to install the RH-50 back. I see the 4 pins at the sides, , the two conical things, and the lock slides with arrows pointing down, but nothing wants to move. I also see 4 small screws on the slides. It acts like the locks are really tightly locked. Any suggestions?

GW,
The back is a standard Graflok, 2 chrome horizontal arms above and below pop-up shade....push down on center of both at the same time while sliding the assembly to the right! You have removed the GG frame, now put the film holder into position and use the 2 slider bars to hold it in position!
Bert

I was trying to refer to the removeable graflok back itself, not just the GG/roll holder part which works well. Switching from GG/roll to the rh-50 or polaroid backs requires removal of the entire back assembly.

The back assembly is free now - just VERY tight, but pushing on the conical chrome buttons finally released one side - then the other required the careful application of channel-locks. Now they are lightly greased and moving nicely.